This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2000-084991, filed Mar. 24, 2000, the entire contents of which are incorporated herein by reference.
The present invention relates to a male-type terminal and a connector and an electric-connection structure using the same applicable to a connecting portion of a harness, a fuse block, etc. connected to a large power load used in, for example, an automobile wiring system.
There has conventionally been known a connector for an automobile wire harness that has this type of electric-connection structure. The connector is made by pressing its male-type terminal and a female-type terminal as well as a plate-shaped piece made of copper or copper alloy and then plating them with tin usually. Furthermore, some connector terminals used in an electric automobile are plated partially with silver.
Ecological requirements and demands for improvements in the fuel efficiency in the recent years have been transforming mechanical control into electric control for the automobile equipment. For example, as for the power steering, a so-called electric power steering has been developed for generating power electrically in place of the conventional one for generating power by the rotation of the engine. Accordingly, the current electric load of up to about a few hundred watts is expected to amount to a few kilowatts in the future. Furthermore, from the viewpoint of improving the efficiency of supplying power, the current source voltage of 14V in a vehicle may rise to 42V in the future.
If a user detaches or inserts the connector of a harness connected to a load being supplied with a large power from such a voltage-elevated power source during operation, arc discharge occurs at the tip of a male-type or female-type terminal, which may be melted and lost.
In view of the above, it is an object of the invention to provide a male-type terminal, a connector, and an electric-connection structure which can prevent arc discharge from occurring at an electric connection and hence a melted-and-lost phenomenon of the terminal portion.
A male-type terminal according to a first aspect of the invention comprises a conductor portion inserted to a female-type terminal and a resistor provided on at least the tip of this conductor portion, wherein at the time of insertion to the above-mentioned female-type terminal, switching is made from the above-mentioned resistor to the above-mentioned conductor portion and, at the time of detaching from the above-mentioned female-type terminal, switching is made from the above-mentioned conductor portion to the above-mentioned resistor.
Thus, by the invention, the male-type terminal can be brought into contact with the female-type terminal via the resistor to reduce a load power due to the resistor, thus effectively suppressing the occurrence of arc discharge to prevent the terminal from being melt and lost.
Additional objects and advantages of the invention will be set forth in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The objects and advantages of the invention may be realized and obtained by means of the instrumentalities and combinations particularly pointed out hereinafter.